The purpose of this research is to evaluate the long-term influence of mass media campaigns designed to prevent the initiation of cigarette smoking by adolescents. The campaigns, guided by behavioral science theory and the premise that they should be cost effective, focus on the consequences expected from smoking behavior and the stimulation of peer involvement. From Standard Metropolitan Statistical Areas (SMSAs) in the Southeast U.S. with fewer than 500,000 inhabitants, 10 will be randomly allocated to receive treatments which reflect increments in intensity and cost: 1. four SMSAs will not receive the campaign (controls), 2. two will receive radio messages which focus on selected expected consequences of smoking and not smoking, 3. two will receive the radio messages plus a component to facilitate peer involvement, and 4. two will receive the messages and peer involvement component via both radio and television. Baseline data will be collected from 223 adolescents and their mothers in each SMSA before the six month mass media campaign. Smoking behavior, the expected consequences of that behavior, and antecedent and mediator variables will be measured. One year after the campaign the measures will be repeated with the same subjects. Interim measures for a subsample of 50 subjects in each SMSA will be taken within one month after the campaign to assess awareness of the campaign and to provide estimates of early campaign effects. In addition to comparisons of experimental and control groups, and comparisons of experimental groups, analyses will determine if campaign effects vary according to mediating variables. The findings will be considered in the context of preventing the onset of adolescent smoking.